Kerry told students Monday at prestigious Korea University that authoritarian Pyongyang, with the lowest rate of access to the Web in the world, was the opposite of ultra-wired, democratic Seoul.
Kerry linked poor Internet freedom to questionable human rights and a stifled economy without innovation or freely exchanged ideas.
Washington accuses Pyongyang of being behind last year's massive hack of Sony Pictures over a film that centred on the assassination of North Korean leader Kim Jong Un. Seoul also says Pyongyang has staged a series of hacks on major South Korean companies and government organizations. Pyongyang denies the hacking claims.